In recent years, an image forming apparatus using an electrophotographic technology is functionally required to be capable of printing on a variety of image receiving media.
The image receiving medium, referring to a medium, is a printed medium such as a sheet or an OHP (overhead projector) film.
In the image forming apparatus, a transfer condition is changed with the material type and the thickness of a medium. The image forming apparatus prepares different modes for different media in advance according to different transfer conditions.
The modes refer to print modes. The image forming apparatus provides a mode for printing on a medium having a standard thickness or a mode for printing on a medium thicker or thinner than the standard thickness.
The image forming apparatus switches to a transfer condition proper for a medium according to the mode selected by the user on a control panel.
In methods for switching between transfer conditions, if the current medium meets the transfer condition assumed in a selected mode, then a user-desired transfer quality can be achieved.
However, a medium not assumed according to the selected mode is set by the image forming apparatus in the mode. A transfer job is carried out on the medium under a transfer condition different from that for the mode. Consequentially, no excellent transfer performance is achieved by the image forming apparatus.
Alternatively, the user mistakenly selects a button which corresponds to the type of the image receiving medium. Because of the error operation of the user, the image forming apparatus prints in a medium mode not corresponding to type of the image receiving medium. Consequentially, no accurate transfer performance is achieved by the image forming apparatus.
If a transfer apparatus cannot exert a transfer performance accurately, then an image forming apparatus cannot form an optimal image.